2. Categories

      Applications: Art, Cardiology, Dentistry, Dermatology, Developmental Biology, Gastroenterology, Gynecology, Microscopy, NDE/NDT, Neurology, Oncology, Ophthalmology, Other Non-Medical, Otolaryngology, Pulmonology, Urology
      Business News: Acquisition, Clinical Trials, Funding, Other Business News, Partnership, Patents
      Technology: Broadband Sources, Doppler, Probes, Tunable Sources
      Miscellaneous: Jobs & Studentships, Student Theses, Textbooks

  3. Share your journal articles, press releases, job & studentship openings, and more with the OCT community. Click here.

  4. Subscribe to OCTNews Daily or Weekly Newsletter

  5. OCT Business Advice

  6. Organizations in the News

    (2 articles) University of Tsukuba

    (2 articles) FDA

    (1 articles) University of Hong Kong

    (1 articles) Gwangju Institute of Science and Technology

    (1 articles) VU University Amsterdam

    (1 articles) Zhejiang University

    (1 articles) Centre Hospitalier Intercommunal de Créteil

    (1 articles) University of Texas Health Science Center

    (1 articles) Massachusetts Eye and Ear Infirmary

    (1 articles) The Chinese University of Hong Kong

  7. People in the News

    (2 articles) Yoshiaki Yasuno

    (2 articles) Shuichi Makita

    (1 articles) Sergey G. Proskurin

    (1 articles) Roman V. Kuranov

    (1 articles) Anant Agrawal

    (1 articles) Brendan F. Kennedy

    (1 articles) Daniel J. Starks

    (1 articles) Myeong Jin Ju

    (1 articles) Kakarla V. Chalam

    (1 articles) Eric H. Souied

  8. OCT Companies in the News

    (2 articles) Heidelberg Engineering

    (1 articles) Avinger

    (1 articles) St. Jude Medical

    (1 articles) LenSx

    (1 articles) OptiMedica

    (1 articles) Carl Zeiss Meditec

    (1 articles) Terumo Cardiovascular Systems

    (1 articles) Optovue

  9. OCT Products in the News

    (4 articles) Heidelberg Spectralis

    (1 articles) Optovue RTVue-100

    (1 articles) Zeiss Stratus OCT

    (1 articles) Zeiss Cirrus HD-OCT

  10. Picture Gallery

  11. Popular Articles This Week

  12. Popular Articles This Month

  13. Advice to Students from Leaders in the Optics and Photonics Community

  14. Recent Quotes

    1. “ We're looking forward to transmitting two live cases from Muenster to this year's LINC audience. ”
      By John B. Simpson
    2. “ The speed at which our team developed these prototypes is outstanding, thanks to our in-house nanophotonics experts and the contribution of Professor Lipson and the Cornell Nanofabrication Facility...We are well underway to release our commercial unit by the end of this calendar year, targeting an axial resolution of less than 6um with over 100um bandwidth, in a very small form factor. ”
      By Stefan Larson
    3. “ Axsun Industrial segment revenues, which were approximately $1.5 million in the fourth quarter of 2011 versus revenues of $5.1 million in the fourth quarter a year ago, or a decline of approximately 70 percent. ”
      By Scott Huennekens
    4. “ Early EU commercial cases are showing remarkable patient outcomes...Avinger’s global product portfolio has already helped physicians treat more than 5000 patients suffering from PAD. We’re committed to making sure all people suffering from this epidemic can have access to our advanced technologies. ”
      By John B. Simpson
    5. “ Earning a CE Mark is an important milestone for Bioptigen, but it's even more meaningful for the pediatric and adult patients who now can benefit from our more flexible imaging platform. We bring imaging to the patient; the patient doesn't have to come to us. ”
      By Eric L. Buckland
    6. “ Physicians in Europe play a critical role when it comes to advancing non-invasive medical technologies...Bioptigen looks forward to collaborating with these professionals as they develop new best practices based on standards that benefit patients worldwide. ”
      By Eric L. Buckland
    7. “ The Clayton Foundation allows its investigators wider latitude in their research than traditional grant-funding agencies...As a result, rather than focusing on research that will lead to the next funded grant application, investigators can focus on what is most exciting and most likely to impact patient care. ”
      By Marc D. Feldman
    8. “ OCT is one of the most promising and exciting medical imaging technologies available today...The detail of information OCT can provide is simply astonishing and will continue to impact not only cardiology but other medical disciplines, such as ophthalmology. ”
      By Thomas E. Milner
    9. “ "The Series A financing is a major achievement for MedLumics that aligns us with top-tier life science investment partners who believe in the tremendous potential of our microchip-based OCT technology...We believe this investment speaks to the exceptional clinical value it will ultimately bring to physicians and patients. ”
      By Eduardo Margallo Balbás
    10. “ We noticed that signal processing was becoming the major bottleneck for SS-OCT imaging...We identified GPUs as a low cost and ubiquitous signal processing resource and went about creating a framework that allows our customers to easily use it in combination with our PCI Express waveform digitizers ”
      By Muneeb Khalid

  1. Feature Of The Week: In vivo depth-resolved oxygen saturation by dual-wavelength photothermal (DWP) OCT

    All mammalian tissues need oxygen for survival. The human body has a delicately organized vascular network that supplies our tissue with oxygen and other nutrients as well as removing waist products. Not surprisingly, aberrations in vascular oxygen supply are implicated in at least 70 diseases and that number continues to grow. The oxygen distribution from vascular hemoglobin to the parenchymal cells begins with oxygen diffusion first from arterioles with diameters less than 50 µm, and second from capillaries, with deoxygenated blood draining back to venules where the blood is redirected to the lungs for re-oxygenation.

    The earliest abnormalities in oxygen exchange take place at the capillary level and these can often be discerned clinically from hemoglobin oxygen saturation (SaO2) levels in arterioles and venules. Oxygen saturation (SaO2) levels in individual capillaries is frequently too diffuse and requires a great deal of processing and is not easy to interpret, while information from larger (> 50 µm diameter) arteries and veins can be dominated by nearby healthy tissue which mask localized pathology. Conversely, information acquired from target arterioles and venules ranging in diameters from 10-50 µm can provide relatively localized and early signs of oxygen delivery abnormalities that can be valuable for making clinically meaningful conclusions.

    Current approaches to assess microvascular blood oxygenation include: a) invasive approaches such as oxygen-sensitive microelectrode techniques; b) minimally invasive methods with resolution coarser than 50 µm such as phosphorescence quenching imaging of exogenous oxygen sensitive dyes; c) non-invasive without depth resolution such as spectroscopic oximetry; and d) non-invasive with resolution coarser than 50 µm such as functional MRI and photoacoustic imaging.

    Spectroscopic Fourier Domain Optical Coherence Tomography (SFD-OCT) has been reported to measure depth-resolved microvasculature SaO2 levels in phantoms and tissue. However, the variation and complexity of light scattering by blood and tissue limits SaO2 sensitivity of intensity-based SFD-OCT and complicates clinical translation. Recently, our group reported a Dual Wavelength Photothermal (DWP) OCT approach to measure depth-resolved microvasculature SaO2 levels in phantom blood vessels.

    In DWP-OCT, incident photothermal excitation light at two distinct wavelengths is absorbed by target chromophores in a sample resulting in thermally-induced optical pathlength (op) variations that are measured with a phase-sensitive OCT system. Relative concentration of the two target chromophores can be estimated from the normalized ratio of op variations at the photothermal excitation wavelengths. Recently, we extended DWP-OCT to depth-resolved in vivo measurement of SaO2 levels in a 30 µm arteriole in a murine animal model. We believe that DWP OCT instrumentation can provide clinical and biomedical researchers with a powerful tool to improve our understanding of basic pathophysiological processes underlying the natural history of various diseases as well as biomarkers to detect the earliest stages of the disease before irreversible changes have occurred and allow monitoring of long-term progression and effectiveness of selected therapeutic interventions.

    DWP OCT estimation of SaO2 levels relies on measuring optical pathlength (op) that light experiences while traveling from the probe to specific tissue layers and back to the probe. Since op is not influenced by intensity fluctuation as in intensity based spectroscopic methods we believe that further development of DWP OCT will provide an important candidate approach to image microvasculature SaO2 levels for fundamental biomedical research and clinical instrumentation.

    For more information see recent Article. Courtesy Roman V. Kuranov from University of Texas Health Science Center. To share this article click Here.

  2. Featured Articles

    1. OCT Phantoms Initiative: A new effort to bring standardized tools for OCT system characterization and validation to the community

      Explore Optical Coherence Tomography News (5 hours, 19 min ago)

      OCT Phantoms Initiative: A new effort to bring standardized tools for OCT system characterization and validation to the community Over the past two decades, the capabilities, applications, and usage of OCT have advanced remarkably. Given the maturity of OCT, there is an imminent need for widely available and standardized tools to benchmark OCT device performance. Controlled test objects, generally known as phantoms, are essential to satisfy this need by serving as a stable, well-characterized reference which is periodically imaged. The proper phantom can ensure data accuracy and consistency over time, among multiple instruments, and across device manufacturers. This is a key step towards standardization and quality assurance on par with the most established medical imaging modalities. The OCT Phantoms ... (Read Full Article)

      Comment Mentions:   University of London   Pete H. Tomlins   University of Western Australia

    2. Photonic Generation and Wireless Transmission of Linearly/Nonlinearly Continuously Tunable Chirped Millimeter-Wave Waveforms with High Time-Bandwidth Product at W-band

      Explore IEEE Xplore (5 hours, 36 min ago) Tunable Sources

      Photonic Generation and Wireless Transmission of Linearly/Nonlinearly Continuously Tunable Chirped Millimeter-Wave Waveforms with High Time-Bandwidth Product at W-band We demonstrate a novel scheme for photonic generation of chirped millimeter-wave (MMW) pulse with ultra-high time-bandwidth product (TBP). By using a fast wavelength sweeping laser with a narrow instantaneous linewidth, wideband/high-power photonic transmitter-mixers, and heterodyne beating technique, continuously tunable chirped MMW waveforms at W-band are generated and detected through wireless transmission. Compared with the reported optical grating based wavelength-to-time mapping techniques for chirped pulse generation, our approach eliminates the problem in limited frequency resolution of grating, which seriously limits the continuity, tunability, and TBP of the generated waveform. Furthermore, by changing the alternating current (AC) waveform of the driving signal ... (Read Full Article)

      Comment

    3. Reproducibility of Retinal Blood Flow Measurements Derived From Semi-Automated Doppler OCT Analysis

      Explore SLACK Journals (6 hours, 10 min ago) Ophthalmology

      Reproducibility of Retinal Blood Flow Measurements Derived From Semi-Automated Doppler OCT Analysis BACKGROUND AND OBJECTIVE: To evaluate reproducibility and intergrader agreement of total retinal blood flow (TRBF) measurements obtained by semi-automated grading of Doppler Fourier-domain optical coherence tomography (FD-OCT) scans. PATIENTS AND METHODS: Doppler FD-OCT scans were obtained from 20 eyes of 18 subjects (10 glaucomatous, 10 normal). Scans were obtained using a circumpapillary scan protocol and analyzed using the Doppler OCT of Retinal Circulation software (version 2). Two masked, independent human graders manually refined the scans, adding or deleting vessels, changing vessel boundaries, and classifying vessels as veins or arteries. TRBF was calculated automatically by software summing flow in all veins. ... (Read Full Article)

      Comment Mentions:   Optovue   David Huang   Heidelberg Engineering

    4. Frontiers in optical imaging of cerebral blood flow and metabolism

      Explore Nature Publishing Group (6 hours, 17 min ago) Doppler

      Frontiers in optical imaging of cerebral blood flow and metabolism In vivo optical imaging of cerebral blood flow (CBF) and metabolism did not exist 50 years ago. While point optical fluorescence and absorption measurements of cellular metabolism and hemoglobin concentrations had already been introduced by then, point blood flow measurements appeared only 40 years ago. The advent of digital cameras has significantly advanced two-dimensional optical imaging of neuronal, metabolic, vascular, and hemodynamic signals. More recently, advanced laser sources have enabled a variety of novel three-dimensional high-spatial-resolution imaging approaches. Combined, as we discuss here, these methods are permitting a multifaceted investigation of the local regulation of CBF and metabolism with unprecedented ... (Read Full Article)

      Comment Mentions:   Vivek J. Srinivasan   Massachusetts General Hospital   University of Pennsylvania

    5. Natural History of Stent Edge Dissection, Tissue Protrusion and Incomplete Stent Apposition Detectable Only on Optical Coherence Tomography After Stent Implantation

      Explore jstage.jst.go.jp (6 hours, 43 min ago) Cardiology

      Natural History of Stent Edge Dissection, Tissue Protrusion and Incomplete Stent Apposition Detectable Only on Optical Coherence Tomography After Stent Implantation Background: The clinical impact of stent edge dissection, tissue protrusion, and incomplete stent apposition (ISA) after stent implantation, detectable only on optical coherence tomography (OCT), is still unknown because the natural course has not been investigated. Methods and Results: All consecutive patients with angina pectoris in whom both intravascular ultrasound (IVUS) and OCT were performed immediately after stenting and at follow-up were included in the present study. The natural history of OCT-detected stent edge dissection, tissue protrusion, and ISA during follow-up was investigated. A total of 36 patients with 39 lesions was analyzed. At baseline, OCT showed 12 stent edge ... (Read Full Article)

      Comment Mentions:   Lightlab M3 Imaging Console   Kawasaki Medical School   Hiroyuki Okura

    6. Optical Coherence-domain Imaging of Subcutaneous Human Blood Vessels in vivo

      Explore sapub.org (Jan 26 2012) Dermatology

      Optical Coherence-domain Imaging of Subcutaneous Human Blood Vessels in vivo Experimental methods of Optical Coherence Tomography (OCT) are applied for two-dimensional mapping of subcutaneous human blood vessels. Structural images of in vivo human finger and human palm macro vessels (0.2-1.0 mm) before and after optical clearing using the modified low power rapid scanning optical delay line are presented. Images are scanned with 12 µm minimum spatial resolution. The described modifications enable to apply low power (0.4-0.5 mW), low noise broadband near infrared light source and to obtain structural images with detection of not only reflected but also multiply scattered coherence-gated photons. The achieved transcutaneous probing depth is about 1.6-1.8 mm (Read Full Article)

      Comment Mentions:   Wolfgang Drexler   Sergey G. Proskurin

    7. Alzheimer's Disease and Glaucoma: Imaging the Biomarkers of Neurodegenerative Disease

      Explore Hindawi Publishing Corporation (Jan 26 2012) Neurology , Ophthalmology

      Alzheimer's Disease and Glaucoma: Imaging the Biomarkers of Neurodegenerative Disease Imaging through the visual system in Alzheimer's disease, with the technology currently in widespread use for the diagnosis and management of eye disease such as glaucoma and macular degeneration, is proving to be promising. In vivo cross-section imaging during an annual comprehensive eye exam has been available for a decade for glaucoma and macular degeneration, and this same imaging, using Optical Coherence Tomography, has been demonstrated to show deficits specific to AD and mild cognitive impairment. These deficits are in the form of nerve fiber layer tissue drop out in the retina and optic nerve. The retrograde loss of nerve ... (Read Full Article)

      Comment Mentions:   Denise A. Valenti

    8. Integrated Tunable Quantum-Dot Laser for Optical Coherence Tomography in the 1.7 um Wavelength Region

      Explore IEEE Xplore (Jan 24 2012) Tunable Sources

      Integrated Tunable Quantum-Dot Laser for Optical Coherence Tomography in the 1.7 um Wavelength Region In this paper, we present the design and characterization of a monolithically integrated tunable laser for optical coherence tomography in medicine. This laser is the first monolithic photonic integrated circuit containing quantum-dot amplifiers, phase modulators, and passive components. We demonstrate electro-optical tuning capabilities over 60 nm between 1685 and 1745 nm, which is the largest tuning range demonstrated for an arrayed waveguide grating controlled tunable laser. Furthermore, it demonstrates that the active-passive integration technology designed for the 1550 nm telecom wavelength region can also be used in the 1600–1800 nm region. The tunable laser has a 0.11 nm effective linewidth ... (Read Full Article)

      Comment Mentions:   Zhejiang University

    9. Thermal resistance reduction in high power superluminescent diodes by using active multi-mode interferometer

      Explore Applied Physics Letters (Jan 19 2012) Broadband Sources

      Thermal resistance reduction in high power superluminescent diodes by using active multi-mode interferometer Low thermal resistance of high power superluminescent diodes (SLEDs) by using active multi-mode interferometer (active-MMI) is presented in this paper. The active layer temperature evaluation demonstrates that the power saturation mechanism in active-MMI SLED is heat for the first time. Low thermal resistance of 4.83 K/W in active-MMI SLEDs leads to a high power of 115 mW. Moreover, the effect of the active area size on the output power is demonstrated both experimentally and theoretically. Good agreement between the theoretical and experimental results indicates that active-MMI configuration is a new design in support of efficient heat dissipation and thermal resistance ... (Read Full Article)

      Comment Mentions:   Exalos   Kyushu University

    10. New EXALOS High-Performance 1550-nm Swept Sources to Address Fiber-Optic Sensing and Optical Coherence Tomography Imaging Applications

      Explore Optical Coherence Tomography News (Jan 18 2012) Other Business News , Tunable Sources

      New EXALOS High-Performance 1550-nm Swept Sources to Address Fiber-Optic Sensing and Optical Coherence Tomography Imaging Applications Exalos Press Release - EXALOS AG is announcing during BiOS / Photonics West the introduction of another member of the RapidSweep Swept Source family. With customizable tuning ranges (up to 200nm) and sweep frequencies (from 2 kHz to 150 kHz) in the 1550-nm spectrum, the ESS-1550 Swept Sources offer flexible system designs for applications in fiber-optic sensing and swept source Optical Coherence Tomography imaging. For system integration the Swept Source is delivered with complete driver electronics, customized OEM packages are available upon request. RapidSweep Swept Source – a high-end sweeping laser with a small footprint. (Read Full Article)

      Comment Mentions:   Exalos

    11. Cracking Open the Scientific Process

      Explore The New York Times (Jan 17 2012)

      Cracking Open the Scientific Process The New England Journal of Medicine marks its 200th anniversary this year with a timeline celebrating the scientific advances first described in its pages: the stethoscope (1816), the use of ether for anesthesia (1846), and disinfecting hands and instruments before surgery (1867), among others. For centuries, this is how science has operated — through research done in private, then submitted to science and medical journals to be reviewed by peers and published for the benefit of other researchers and the public at large. But to many scientists, the longevity of that process is nothing to celebrate. (Read Full Article)

      Comment

    12. Optical coherence microscopy for deep tissue imaging of the cerebral cortex with intrinsic contrast

      Explore opticsinfobase.org (Jan 17 2012) Microscopy

      Optical coherence microscopy for deep tissue imaging of the cerebral cortex with intrinsic contrast In vivo optical microscopic imaging techniques have recently emerged as important tools for the study of neurobiological development and pathophysiology. In particular, two-photon microscopy has proved to be a robust and highly flexible method for in vivo imaging in highly scattering tissue. However, two-photon imaging typically requires extrinsic dyes or contrast agents, and imaging depths are limited to a few hundred microns. Here we demonstrate Optical Coherence Microscopy (OCM) for in vivo imaging of neuronal cell bodies and cortical myelination up to depths of ~1.3 mm in the rat neocortex. Imaging does not require the administration of exogenous dyes or ... (Read Full Article)

      Comment Mentions:   Thorlabs   Alex E. Cable   Vivek J. Srinivasan

    13. Postdoctoral & Research Associate Positions at Nanyang Technological University, Singapore

      Explore Optical Coherence Tomography News (Jan 16 2012) Jobs & Studentships

      Postdoctoral & Research Associate Positions at Nanyang Technological University, Singapore Position description: One year full-time research positions (1 Research Associate, 1 Postdoctorate Research Fellow), with possibility of extension, are available in the School of Electrical and Electronic Engineering at the Nanyang Technological University in Singapore (www.ntu.edu.sg/eee ). The successful candidate is expected to develop novel image processing methods for monitoring and screening ocular diseases using high definition optical coherence tomography. Qualifications: (1)BEng/Master degree for the Research Associate position or PhD for the Postdoctorate/Research Fellow position in Electrical & Electronic, Computer, Biomedical Engineering or related fields. (2)Hands-on experience in biomedical image processing. (3)Strong Matlab or C++ programming skills are preferred. (4)Excellent ... (Read Full Article)

      Comment Mentions:   Nanyang Technological University   Pina Marziliano

    14. Tornado Medical Systems Showcases OCT-On-Chip Prototype at Photonics West

      Explore Optical Coherence Tomography News (Jan 14 2012) Other Business News

      Tornado Medical Systems Showcases OCT-On-Chip Prototype at Photonics West Tornado Medical Systems Press Release - Meeting the need for smaller, cheaper, and more reliable OCT devices, Tornado Medical System is developing the first commercially available OCT system on a chip. Using commercial integrated optics technologies initially developed in the laboratory of Professor Michal Lipson at Cornell University, a MacArthur “Genius” Fellow recently appointed to the company’s Advisory Board, Tornado’s Ithaca based team has developed a compact prototype with a 12um axial resolution and 65nm bandwidth. Tornado’s fully integrated nanophotonics approach will significantly decrease system cost, while providing the robustness that comes with a no-moving-parts design. Tornado will showcase its ... (Read Full Article)

      Comment Mentions:   Cornell University   Tornado Medical Systems   Stefan Larson

    15. Effect of multimodal coupling in imaging micro-endoscopic fiber bundle on optical coherence tomography

      Explore SpringerLink Home (Jan 13 2012) Gastroenterology

      Effect of multimodal coupling in imaging micro-endoscopic fiber bundle on optical coherence tomography The effect of higher-order modes in fiber bundle imager-based optical coherence tomography (OCT) has been theoretically modeled using coupled fiber mode analysis ignoring the polarization and core size variation in order to visualize the pure effect of multimodal coupling of the imaging bundle. In this model, the optical imaging fiber couples several higher-order modes in addition to the fundamental one due to its high numerical aperture for achieving light confinement to the single core pixel. Those modes become evident in a distance domain using A-mode (depth) OCT based on a mirror sample experiment where multiple peaks are generated by the ... (Read Full Article)

      Comment Mentions:   Johns Hopkins University   Jin U. Kang   Korea University

    16. In vivo characterisation of bioresorbable vascular scaffold strut interfaces using optical coherence tomography with Gaussian line spread function analysis

      Explore eurointervention.org (Jan 12 2012) Cardiology

      In vivo characterisation of bioresorbable vascular scaffold strut interfaces using optical coherence tomography with Gaussian line spread function analysis Optical coherence tomography (OCT) of a bioresorbable vascular scaffold (BVS) produces a highly reflective signal outlining struts. This signal interferes with the measurement of strut thickness, as the boundaries cannot be accurately identified, and with the assessment of coverage, because the neointimal backscattering convolutes that of the polymer, frequently making them indistinguishable from one another. We hypothesise that Gaussian line spread functions (LSFs) can facilitate identification of strut boundaries, improving the accuracy of strut thickness measurements and coverage assessment. Methods and results: Forty-eight randomly selected BVS struts from 12 patients in the ABSORB Cohort B clinical study and four Yucatan ... (Read Full Article)

      Comment Mentions:   Erasmus Medical Center   Yoshinobu Onuma   Richard Rapoza

    17. Optovue and Carl Zeiss Meditec Have Reached Settlement in Their Current Patent Infringement Disputes

      Explore Optical Coherence Tomography News (Jan 11 2012) Other Business News

      Optovue and Carl Zeiss Meditec Have Reached Settlement in Their Current Patent Infringement Disputes Optovue Inc. and Carl Zeiss Meditec Inc. announced today that they have signed a settlement agreement resolving two pending Federal District Court patent infringement cases. Under the terms of the agreement, the companies dismissed all currently pending litigation and entered into a cross-license agreement of certain issued and to be issued patents owned or controlled by each party. The specific terms of the settlement are confidential. About Optovue®(www.optovue.com) Optovue Inc. is a privately-held ophthalmic device company dedicated to working with eye care professionals and clinical researchers to lead the commercialization of new imaging modalities that improve diagnosis and therapy of ... (Read Full Article)

      Comment Mentions:   Optovue   Carl Zeiss Meditec   Paul Kealey

    18. Quantitative comparison of contrast and imaging depth of ultrahigh-resolution optical coherence tomography images in 800–1700 nm wavelength region

      Explore opticsinfobase.org (Jan 11 2012)

      Quantitative comparison of contrast and imaging depth of ultrahigh-resolution optical coherence tomography images in 800–1700 nm wavelength region We investigated the wavelength dependence of imaging depth and clearness of structure in ultrahigh-resolution optical coherence tomography over a wide wavelength range. We quantitatively compared the optical properties of samples using supercontinuum sources at five wavelengths, 800 nm, 1060 nm, 1300 nm, 1550 nm, and 1700 nm, with the same system architecture. For samples of industrially used homogeneous materials with low water absorption, the attenuation coefficients of the samples were fitted using Rayleigh scattering theory. We confirmed that the systems with the longer-wavelength sources had lower scattering coefficients and less dependence on the sample materials. For a biomedical sample, we ... (Read Full Article)

      Comment Mentions:   Nagoya University   Norihiko Nishizawa

    19. A fiber-based single-unit dual-mode optical Imaging system: Swept source optical coherence tomography and fluorescence spectroscopy

      Explore ScienceDirect (Jan 10 2012) Tunable Sources

      A fiber-based single-unit dual-mode optical Imaging system: Swept source optical coherence tomography and fluorescence spectroscopy We propose a fiber optic single-unit but dual-mode optical imaging system that can provide fast cross-sectional imaging capabilities of swept-source optical coherence tomography (SS-OCT) and functional capabilities of fluorescence spectroscopy (FS). By adopting a fiber optic FS system into a fiber-based SS-OCT system, a compact and effective multimodal single-unit SSOCT-FS system could be achieved. Here, the key element of the proposed multimodal imaging system is a specially designed fiber coupler based on double-clad fiber (DCF), which has only cladding-mode coupling capability. The DCF couplers were fabricated with home-drawn DCF by several fabrication methods; a twisting method, a side-polishing method and ... (Read Full Article)

      Comment Mentions:   Byeong Ha Lee   Hae Young Choi   Gwangju Institute of Science and Technology

    20. Congratulations to Zhao Wang from CWRU a Winner of a 2012 Student Travel Grant Award

      Explore Optical Coherence Tomography News (Jan 9 2012) Cardiology

      Congratulations to Zhao Wang from CWRU a Winner of a 2012 Student Travel Grant Award Zhao Wang from Case Western Reserve University is one of four winners of the OCT News 2012 student travel grant awards (see prior announcement Here). Below is a summary of his work. Coronary artery disease is the leading cause of death worldwide. The rupture of thin-cap fibroatheroma (TCFA) accounts for most acute coronary events. Optical Coherence Tomography (OCT) is able to quantify the fibrous cap (FC) thickness in vivo. Conventional analysis measuring the thinnest part of the FC is subject to inter-observer variability and does not capture the 3-D morphology of the FC. The aim of this study is to ... (Read Full Article)

      Comment Mentions:   Andrew M. Rollins   Case Western Reserve University   Marco A. Costa

    21. Congratulations to Jian Ren from Caltech a Winner of a 2012 Student Travel Grant Award

      Explore Optical Coherence Tomography News (Jan 9 2012) Ophthalmology , Probes

      Congratulations to Jian Ren from Caltech a Winner of a 2012 Student Travel Grant Award Jian Ren from the California Institute of Technology is one of four winners of the OCT News 2012 student travel grant awards (see prior announcement Here). Below is a summary of his work. Glaucoma is one type of ophthalmic diseases, where ocular hypertension damages optical nerve, making it the second leading cause of blindness worldwide. One major cause of Open Angle Glaucoma is the poor outflow of aqueous humor through the Trabecular Meshwork (TM). Potential treatments include the micro-bypass stents, which are implanted in the TM and shunt fluid directly to the Schlemm’s Canal (SC) to reduce intraocular pressure. Implanting ... (Read Full Article)

      Comment Mentions:   California Institute of Technology   Jigang Wu   Changhuei Yang

    22. Congratulations to Giovanni Ughi from K. U. Leuven a Winner of a 2012 Student Travel Grant Award

      Explore Optical Coherence Tomography News (Jan 9 2012) Cardiology

      Congratulations to Giovanni Ughi from K. U. Leuven a Winner of a 2012 Student Travel Grant Award Giovanni Ughi from the Catholic University Leuven is one of four winners of the OCT News 2012 student travel grant awards (see prior announcement Here). Below is a summary of his work. Topic covered by the project is software development for quantitative computer aided automated analysis of intra-vascular OCT images. Automated segmentation of stent struts and lumen, stent apposition, stent coverage and registration of IV-OCT datasets at different instants of times are part of the software research and development. Moreover, tissue characterization to automatically assess atherosclerotic plaques components and morphology are other issues at which the project address. The optical ... (Read Full Article)

      Comment Mentions:   Walter Desmet   K. U. Leuven   Giovanni J. Ughi

    23. Congratulations to Chia-Pin Liang From the University of Maryland a Winner of a 2012 Student Travel Grant Award

      Explore Optical Coherence Tomography News (Jan 9 2012) Neurology , Doppler

      Congratulations to Chia-Pin Liang From the University of Maryland a Winner of a 2012 Student Travel Grant Award Chia-Pin Liang from the University of Maryland is one of four winners of the OCT News 2012 student travel grant awards (see prior announcement Here). Below is a summary of his work. Stereotactic procedures that require insertion of needle-based instruments into the brain serve important roles in a variety of neurosurgical interventions such as biopsy, catheterization, and electrode placement. The laceration of blood vessels in the path of the advancing needle can result in stroke and even death and is perhaps the most worried complication. Also, the brain may shift during surgery because of cerebrospinal fluid (CSF) leakage so that ... (Read Full Article)

      Comment Mentions:   University of Maryland   Yu Chen   Jeremiah Wierwille

    24. Evaluation of structural change and local strain distribution in polymers comparatively imaged by FFSA and OCT techniques

      Explore eXPRESS Polymer Letters (Jan 9 2012) NDE/NDT

      Evaluation of structural change and local strain distribution in polymers comparatively imaged by FFSA and OCT techniques Mechanical material testing combined with optical coherence tomography (OCT) allows for the first time the immediate detection of inner structural changes along with a qualitative observation of the local strain distribution in surface near bulk regions of semitransparent and translucent specimens. In addition to a 3D full field strain analysis (FFSA) system based on digital image correlation (DIC), a customized spectral domain OCT system operating at 1550 nm was applied for investigation. Exemplified by tensile testing of elastomer particle filled polypropylene specimens, local dissimilarity evaluation of the OCT images was performed. The results show the high potential of OCT to ... (Read Full Article)

      Comment Mentions:   David Stifter   Bettina Heise   Zoltan Major

    25. See all articles >>

  3. Recent Articles From Around The Web

    1. A Case of Ocular Toxoplasmosis Imaged with Spectral Domain Optical Coherence Tomography

      Explore ekjo.org (5 hours, 40 min ago) Ophthalmology

      A Case of Ocular Toxoplasmosis Imaged with Spectral Domain Optical Coherence Tomography A 54-year-old man presented with blurred central vision in the right eye of two weeks' duration. On presentation, visual acuity was 40 / 50 in the right eye and fundus examination showed a whitish-yellow inflammatory lesion near an atrophic, pigmented retinochoroidal scar located in the superotemporal quadrant. Serologic assessment was negative for IgM, but serum IgG to toxoplasma was elevated. Spectral domain optical coherence tomography (SD-OCT) revealed increased reflectivity from the inner retinal layer, retinal thickening, and choroidal shadowing while focal posterior hyaloid thickening and detachment were observed in the new lesion. He was treated with trimethoprim/sulfamethoxazole, clindamycin, and prednisone. ... (Read Full Article)

      Comment Mentions:   Carl Zeiss Meditec   Zeiss Cirrus HD-OCT

    2. High-Resolution Fourier-Domain Optical Coherence Tomography Findings in Subretinal Cysticercosis

      Explore LWW Online (5 hours, 44 min ago) Ophthalmology

      High-Resolution Fourier-Domain Optical Coherence Tomography Findings in Subretinal Cysticercosis We preset the optical coherence tomography features of subretinal cysticercosis in a 12-year-old boy with presenting visual acuity of 4/60. (Read Full Article)

      Comment

    3. Performance Improvement and Birefringence Investigation of Spectral Domain Optical Coherence Tomography Using a Modified Arrayed Waveguide Grating

      Explore EEMCS EPrints Service (5 hours, 49 min ago)

      Performance Improvement and Birefringence Investigation of Spectral Domain Optical Coherence Tomography Using a Modified Arrayed Waveguide Grating An arrayed-waveguide grating (AWG) with its high accuracy and stability is a powerful tool for spectral analysis. We investigate its potential for spectral-domain optical coherence tomography (SD-OCT). A silicon-oxynitride-based AWG spectrometer for the 800 nm wavelength range is designed for on-chip SD-OCT systems. By removing the output waveguides of the AWG, the depth range is significantly enhanced. In addition, the effect of polarization dependency of the AWG on sensitivity roll-off is investigated and for partial polarization, a beat effect is observed in the depth ranging measurements, which leads to signal fading at specific depths. (Read Full Article)

      Comment Mentions:   University of Twente   Markus Pollnau   Kerstin Wörhoff

    4. Retinal Nerve Fiber Layer Measurement Variability with Spectral Domain Optical Coherence Tomography

      Explore ekjo.org (5 hours, 54 min ago) Ophthalmology

      Retinal Nerve Fiber Layer Measurement Variability with Spectral Domain Optical Coherence Tomography Purpose To evaluate the effect of the scanning laser ophthalmoscope (SLO) guided re-test mode on short- and long-term measurement variability of peripapillary retinal nerve fiber layer (RNFL) thickness obtained by spectral domain-SLO optical coherence tomography (SD-SLO/OCT). Methods Seventy five healthy eyes were scanned 3 times per day (intra-session variability) by both the SLO guided re-test mode and the independent mode of SD-SLO/OCT. Subjects were scanned 3 times by both modes at visits within a 2-week interval (inter-session variability). For testing longitudinal variability, 3 separate exams were performed over 6 months by both modes. The coefficient of variation (CV), reproducibility coefficient ... (Read Full Article)

      Comment Mentions:   University of Ulsan   Ophthalmic Technologies Spectral OCT/SLO   Sung Yong Kang

    5. Three-Dimensional Evaluation of the Lamina Cribrosa Using Spectral-Domain Optical Coherence Tomography in Glaucoma

      Explore iovs.org (6 hours ago) Ophthalmology

      Three-Dimensional Evaluation of the Lamina Cribrosa Using Spectral-Domain Optical Coherence Tomography in Glaucoma Purpose. To introduce a novel, digital, three-dimensional (3D) reconstruction of the optic nerve head (ONH) and to use this method to evaluate the 3D configuration of the lamina cribrosa (LC) in patients with primary open-angle glaucoma. Methods. Optic discs of 137 eyes of 137 patients with open-angle glaucoma were scanned with enhanced depth-imaging spectral domain-optical coherence tomography (SD-OCT). 3D images of the ONH were then reconstructed from B-scan images using maximum intensity projection (MIP) and texture-based volume rendering (VRT). The performance of the threshold segmentation by MIP and VRT was assessed by comparing the distance of the anterior LC surface ... (Read Full Article)

      Comment Mentions:   Seoul National University   UCSD   Robert N. Weinreb

    6. Optical Coherence Tomography of Radiation Optic Neuropathy

      Explore SLACK Journals (6 hours, 28 min ago) Ophthalmology

      Optical Coherence Tomography of Radiation Optic Neuropathy BACKGROUND AND OBJECTIVE: To quantitatively study morphologic optic disc and retinal changes in patients with radiation optic neuropathy (RON) using optical coherence tomography (OCT). PATIENTS AND METHODS: This study is a retrospective clinical case series of ten patients with acute RON. Each had been treated with palladium-103 ophthalmic plaque therapy for choroidal melanoma. OCT images were taken at the time of the initial RON diagnosis to measure cup depth, cup width, edema, vasculature diameter, and retinal thickness. RESULTS: All patients with acute RON showed optic disc edema, increased optic disc thickness, and decreased optic cup depth. The average papillary retinal ... (Read Full Article)

      Comment Mentions:   New York Eye and Ear Infirmary

    7. Comparison of Macular Thickness in Diabetic Macular Edema Using Spectral-Domain Optical Coherence Tomography and Time-Domain Optical Coherence Tomography

      Explore Hindawi Publishing Corporation (6 hours, 36 min ago) Ophthalmology

      Comparison of Macular Thickness in Diabetic Macular Edema Using Spectral-Domain Optical Coherence Tomography and Time-Domain Optical Coherence Tomography Purpose. To compare the macular thicknesses in diabetic macular edema (DME) measured with spectral-domain optical coherence tomography (SD-OCT) and time-domain (TD) OCT. Patients and Methods. The average macular thicknesses of 50 eyes of 29 patients with DME were measured using SD-OCT and TD-OCT. Results. The mean macular thicknesses measured with TD-OCT and SD-OCT were 4 0 1 . 5 ± 1 1 7 . 8 μm (mean ± SD) and 4 4 6 . 2 ± 1 2 3 . 5 μm, respectively. The macular thicknesses measured with the two devices were well correlated (Pearson's product moment correlation, (Read Full Article)

      Comment

    8. Hyperintense plaque identified by magnetic resonance imaging relates to intracoronary thrombus as detected by optical coherence tomography in patients with angina pectoris

      Explore ehjcimaging.oxfordjournals.org (6 hours, 50 min ago) Cardiology

      Hyperintense plaque identified by magnetic resonance imaging relates to intracoronary thrombus as detected by optical coherence tomography in patients with angina pectoris Aims Many investigators have speculated that hyperintense plaques (HIPs) of the carotid artery on non-contrast T1-weighted imaging (T1WI) in magnetic resonance indicate the presence of mural or intraplaque haemorrhage containing methemoglobin. Coronary plaque imaging with T1WI is challenging, and the clinical significance of coronary HIP on T1WI remains unknown. The aim of this study was to compare HIPs on T1WI with coronary plaque morphology assessed by optical coherence tomography (OCT), which allows us to identify not only plaque rupture, but also fibrous cap thickness and intracoronary thrombus in vivo, in patients with angina pectoris. Methods and results Twenty-six lesions from ... (Read Full Article)

      Comment Mentions:   Lightlab M3 Imaging Console   St. Jude Medical

    9. Diurnal Variation of Choroidal Thickness in Normal, Healthy Subjects Measured by Spectral Domain Optical Coherence Tomography

      Explore iovs.org (7 hours, 14 min ago) Ophthalmology

      Diurnal Variation of Choroidal Thickness in Normal, Healthy Subjects Measured by Spectral Domain Optical Coherence Tomography Purpose. To describe the pattern and magnitude of diurnal variation of choroidal thickness (CT), its relation to systemic and ocular factors, and to determine the intervisit reproducibility of diurnal patterns. Methods. A prospective study was conducted on 12 healthy volunteers who each underwent sequential ocular imaging on two separate days at five fixed, 2-hour time intervals. Spectral domain optical coherence tomography (OCT) with enhanced depth imaging and image tracking was performed using a standardized protocol. Choroidal and retinal thicknesses were independently assessed by two masked graders. CT diurnal variation was assessed using repeated-measures ANOVA. Results. A significant diurnal variation in ... (Read Full Article)

      Comment Mentions:   University of Southern California   Srinivas R. Sadda   Yanling Ouyang

    10. Spectral-Domain Optical Coherence Tomography Enhanced Depth Imaging of the Normal and Glaucomatous Nonhuman Primate Optic Nerve Head

      Explore iovs.org (7 hours, 17 min ago) Ophthalmology

      Spectral-Domain Optical Coherence Tomography Enhanced Depth Imaging of the Normal and Glaucomatous Nonhuman Primate Optic Nerve Head Purpose. To test whether the enhanced depth imaging (EDI) modality improves anterior and posterior lamina cribrosa surface (ALCS and PLCS) visibility compared with conventional spectral-domain optical coherence tomography (SD-OCT). Methods. Conventional and EDI SD-OCT scans were obtained 30 minutes after IOP was manometrically lowered to 10 mm Hg in both eyes of 14 nonhuman primates (NHPs) with unilateral experimental glaucoma (EG). Thirteen horizontal and seven vertical radial B-scans of each SD-OCT data set were delineated by one operator masked to image type. Delineated ALCS and PLCS points were projected to 1 of 100 equal-sized subregions of the neural canal opening ... (Read Full Article)

      Comment Mentions:   Devers Eye Institute   Brad Fortune   Claude F. Burgoyne

    11. Assessment of Differential Pharmacodynamic Effects using Optical Coherence Tomography in Neovascular Age-Related Macular Degeneration

      Explore iovs.org (7 hours, 22 min ago) Ophthalmology

      Assessment of Differential Pharmacodynamic Effects using Optical Coherence Tomography in Neovascular Age-Related Macular Degeneration Purpose: To assess the differential pharmacodynamic effects of bevacizumab (Avastin), pegaptanib (Macugen), and verteporfin photodynamic therapy (PDT), using novel OCT parameters, in a recently completed phase III/IV clinical trial. Methods: Data from 122 patients participating in the Avastin (Bevacizumab) for Choroidal neovascularization (ABC) trial, were evaluated. Stratus OCT images were analyzed using custom software - changes in volume of the neurosensory retina, subretinal fluid (SRF), pigment epithelium detachment (PED), and subretinal tissue, were calculated over the 54-week trial period. Results: Reductions in retinal oedema were more than twice as great from bevacizumab than pegaptanib (-0.82 mm3 versus -0.31 mm3), while ... (Read Full Article)

      Comment Mentions:   University College London   Alexander C. Walsh   University of Southern California

    12. In Vivo Evaluation of Retinal Neurodegeneration in Patients with Multiple Sclerosis

      Explore PLoS ONE (Jan 26 2012) Neurology , Ophthalmology

      In Vivo Evaluation of Retinal Neurodegeneration in Patients with Multiple Sclerosis To evaluate macular morphology in the eyes of patients with multiple sclerosis (MS) with or without optic neuritis (ON) in previous history. Optical coherence tomography (OCT) examination was performed in thirty-nine patients with MS and in thirty-three healthy subjects. The raw macular OCT data were processed using OCTRIMA software. The circumpapillary retinal nerve fiber layer (RNFL) thickness and the weighted mean thickness of the total retina and 6 intraretinal layers were obtained for each (Read Full Article)

      Comment Mentions:   National Institutes of Health   Carl Zeiss Meditec   University of Miami

    13. Catechin prevents severe dyslipidemia-associated changes in wall biomechanics of cerebral arteries in LDLr-/-:hApoB+/+ mice and improves cerebral blood flow

      Explore AJP - Heart and Circulatory Physiology (Jan 26 2012) Doppler

      Catechin prevents severe dyslipidemia-associated changes in wall biomechanics of cerebral arteries in LDLr-/-:hApoB+/+ mice and improves cerebral blood flow Endothelial dysfunction and oxidative stress contribute to the atherosclerotic process that includes stiffening of large peripheral arteries. In contrast, we previously reported a paradoxical increase in cerebrovascular compliance in LDLr-/-: hApoB+/+ atherosclerotic (ATX) mice. We hypothesized that prevention of cerebral artery endothelial function with a chronic dietary antioxidant intake would normalize the changes in cerebral artery wall structure and biomechanics and prevent the decline in basal cerebral blood flow (CBF) associated with atherosclerosis. Three-month old ATX mice were treated, or not, for 3 months with the polyphenol (+)-catechin (CAT, 30 mg/kg/day) and compared to wild-type (WT) controls. In isolated pressurized ... (Read Full Article)

      Comment Mentions:   University of Montreal   Ecole Polytechnique de Montréal

    14. Analysis of progression of reticular pseudodrusen by spectral domain optical coherence tomography

      Explore iovs.org (Jan 26 2012) Ophthalmology

      Analysis of progression of reticular pseudodrusen by spectral domain optical coherence tomography Purpose: To analyze reticular pseudodrusen progression using SD-OCT. Methods: Thirty-three consecutive patients (48 eyes) underwent Spectralis SD-OCT using the eye-tracked follow-up protocol 24+/-2 months after baseline examination. Each pair of B-scans (only 1 per eye was evaluated among those showing pseudodrusen progression) was compared with respect to pseudodrusen appearance and retinal layers structure. Stage 1 pseudodrusen was defined as granular material between the RPE and the IS/OS, stage 2 as mounds of material sufficient to alter the contour of the IS/OS, stage 3 as thicker material adopting a conical appearance and breaking through the IS/OS, and stage 4 as fading ... (Read Full Article)

      Comment Mentions:   Heidelberg Spectralis   Centre Hospitalier Intercommunal de Créteil   Eric H. Souied

    15. The physiological variation of the retinal nerve fibre layer thickness and macular volume in humans as assessed by spectral-domain optical coherence tomography

      Explore iovs.org (Jan 26 2012) Ophthalmology

      The physiological variation of the retinal nerve fibre layer thickness and macular volume in humans as assessed by spectral-domain optical coherence tomography Purpose With the introduction of spectral domain optical coherence tomography (SD-OCT), changes in the retinal nerve fibre layer (RNFL) thickness and macular volume (MV) can be detected with a high precision. This study aimed to determine whether there is a physiological quantifiable degree of variation of these structures in humans. Methods This study took place during a 10 km charity run at VU University Amsterdam. Weight, height, hydration status, RNFL thickness (ring scan,12 degrees around the optic nerve head) and MV (20x20 degrees) were assessed in all 69 subjects (44 runners, 25 controls) using the Heidelberg Spectralis with eye-tracking function. ... (Read Full Article)

      Comment Mentions:   University College London   Heidelberg Spectralis   VU University Amsterdam

    16. See all articles >>